Templates are used in many industries to provide an easy method for repetitive activities. For example, a template can be used to repetitively locate the position of holes that need to be drilled in a surface. The template is formed to fit over the surface in a particular position and has holes preformed in the template that will automatically locate the position where holes need to be drilled. A drill bit can then be positioned in the holes in the template to drill the holes at the desired locations in the surface. The template removes the need to measure all the desired locations of the holes in the surface. Once the template is positioned on the surface, the location of the holes in the underlying surface is automatically determined.
To prevent unnecessary wear of the template, bushings have been used. The bushings are configured to mount within the holes in the template and accept a drill bit. The bushings are normally made of metal and have an outside diameter generally equal to or slightly greater than the diameter of the template hole. The bushings prevent the drill bit from contacting the template. As will be appreciated, if the drill bit contacted the template, the hole would be distorted and the template would not be acceptable for further use.
The problem with known bushings is that they can spin within the template openings, push through the template, or be removed from the template when the drill bit is removed. Any of these have the potential for damaging the template and preventing its additional use. Even if the template is not damaged, the time involved in re-installing the bushings is undesirable.
This has been found to be a big problem in industrial applications, particularly for example in the aerospace industry. Large templates with numerous guide holes are used to drill holes in for example wing parts. With numerous guide holes having numerous bushings, any single bushing can push through, rotate, etc. This will result in down time to repair that bushing, or if the failure is severe enough to repair the template. Since there are a large number of bushings that can potentially fail, any number could fail at different times, requiring repeated repairs and long cumulative downtimes.
What is needed is a bushing that is fixed within the template and does not rotate, spin, pull through or push through.